FIX: Parsing a filter chain for the new filter-only expansions: parse them backwards and use "," as filter-chain separator here. This allows using filter chains in filter-only expansions also.

include .hg* *.txt requirement* pyproject.toml
include configmix/*.c configmix/*.h
graft docs
graft tests
graft windows-dev
prune docs/_build
exclude __*
global-exclude *.pyc *.pyo